The present invention relates generally to hand strapping tools used to tension and seal overlapping end portions of strapping material which is disposed around articles or packages which are to be secured or bound by the strapping material, and more particularly to a new and improved gripper plug which is to be used in conjunction with the tensioning wheel of the hand strapping tool so as to provide the overlapped end portions of the strapping material with the requisite amount of tension and yet facilitate the removal of the hand strapping tool from its engaged position with respect to the overlapped end portions of the strapping material once the overlapped end portions have in fact been tensioned and sealed by the hand strapping tool.
Hand strapping tools for tensioning and sealing overlapping end portions of strapping material which is to be disposed around articles or packages which are to be secured or bound by the strapping material are of well known. A typical PRIOR ART hand strapping tool of the aforenoted type, that is, a hand strapping tool which is to be used for tensioning and sealing overlapping end portions of strapping material to be disposed around articles or packages which are to be secured or bound by the strapping material, is partially schematically disclosed within FIG. 1 and is generally indicated by the reference character 10.
More particularly, a package or article to be secured or bound by strapping material in the well-known manner is disclosed at 12, and the strapping material is disclosed at 14. Strapping material 14 is disposed around the article or package 12 so as to encircle the same, and accordingly, overlapped end portions 16,18 of the strapping material 14 are disposed, for example, above and in a spaced relationship with respect to the upper surface 20 of the package or article 12. The hand strapping tool 10 comprises a base member 22 which is adapted to be seated, for example, upon the upper surface 20 of the package or article 12 so as to in effect be interposed between the upper surface 20 of the package or article 12 and the overlapped end portions 16,18 of the strapping material 14, and the base member 22 is fixedly provided with an upwardly projecting lower punch or sealing die assembly 24 which is therefore adapted to engage the undersurface portion of the lower one of the overlapped end portions 16,18 of the strapping material 14. A plurality of vertically movable, upper punch or sealing die members 26 are disposed above the upper surface portion of the upper one of the overlapped end portions 16,18 of the strapping material 14, and accordingly, when the overlapped end portions 16,18 of the strapping material 14 have been properly or sufficiently tensioned with respect to each other, the upper punch or die members 26 are moved downwardly into engagement with the overlapped end portions 16,18 of the strapping material 14 whereby as a result of the operative cooperation defined between the upper punch or die members 26 and the lower punch or sealing die assembly 24, the overlapped end portions 16,18 of the strapping material 14 are secured or sealed together, for example, in a suitable crimped manner.
In order to achieve the aforenoted proper or sufficient tensioning of the overlapped end portions 16,18 of the strapping material 14, the hand strapping tool 10 further comprises a lower gripper member 28 which is also fixedly mounted upon the base member 22 and is adapted to be disposed beneath the lower one of the overlapped end portions 16,18 of the strapping material 14 when the base member 22 is inserted between the upper surface portion 20 of the package or article 12 and the overlapped end portions 16,18 of the strapping material 14. In addition, an upper, vertically movable rotatable tensioning wheel 30 is disposed above the upper one of the overlapped end portions 16,18 of the strapping material 14, and consequently, when the overlapped end portions 16,18 of the strapping material 14 are to be tightly or appropriately tensioned with respect to the article or package 12, upper tensioning wheel 30 is moved downwardly in order to operatively engage the overlapped end portions 16,18 of the strapping material 14 and cooperate with the fixed lower gripper member 28 by effectively gripping or engaging the overlapped end portions 16,18 of the strapping material 14 therebetween. Both the lower gripper member 28 and the upper tensioning wheel 30 are respectively provided with suitable gripping teeth 32,34, and accordingly, upon rotation of the tensioning wheel 30 in the counter-clockwise (CCW) direction, the gripping teeth 32,34 of the lower gripper member 28 and the upper tensioning wheel 30 engage the respective overlapped end portions 16,18 of the strapping material 14 and cause the overlapped end portions 16,18 of the strapping material 14 to be suitably tightened and tensioned with respect to each other, whereupon the upper and lower punch or sealing die members or components 26, 24 can then be actuated in the aforenoted manner with respect to each other so as to in fact achieve the aforenoted crimped securing or sealing of the overlapped end portions 16,18 of the strapping material 14. Upon completion of the securing or sealing operation performed upon the overlapped end portions 16,18 of the strapping material 14, the upper punch or die members 26 and the upper tensioning wheel 30 can be moved back or returned to their upper retracted positions whereupon the hand strapping tool 10 can then be removed from the strapped or bound article or package 12.
While the aforenoted hand strapping tool 10 has of course been generally or substantially satisfactory in connection with its service or performance of the tensioning or tightening, and subsequent securing or sealing, of strapping material 14 upon articles or packages 12, it has in fact been discovered or experienced, however, that such conventional hand strapping tools 10 do have operative drawbacks or disadvantages. For example, in view of the fact that the overlapped end portions 16,18 of the strapping material 14 are tightly engaged or tensioned around the package or article 12, and therefore, more particularly, in view of the fact that the overlapped end portions 16,18 of the strapping material 14 are similarly tightly engaged with the lower punch or sealing die assembly 24 as well as with the lower gripper member 28, it is often difficult to readily remove the hand strapping tool 10 from its operatively engaged position with respect to the article or package 12 and the overlapped end portions 16,18 of the strapping material 14.
In addition, each time the hand strapping tool 10 is in fact removed from an operatively engaged position with respect to an article or package 12 and its associated overlapped end portions 16, 18 of strapping material 14, relative sliding movement, under highly tightened or tensioned conditions, occurs between the undersurface portion of the lower overlapped end portion 16 of the strapping material 14 and the upper surfaces of the lower gripper member teeth 32. Accordingly, over a relatively short period of time wherein the hand strapping tool 10 is employed during operative cycles for tensioning and sealing overlapped end portions 16,18 of strapping material 14 around packages or articles 12, the upper gripping or biting surfaces of the lower gripper member teeth 32 tend to become dulled thereby decreasing their gripping or biting ability or function and thus necessitating frequent replacement of the lower gripper member 28 in order to properly maintain the tensioning or tightening functions of the lower gripper member 28 with respect to the lower end portion 16 of the overlapped end portions 16,18 and in operative conjunction with the upper tensioning wheel 30.
In order to overcome the various operational disadvantages or drawbacks characteristic of the conventional PRIOR ART hand strapping tool 10 disclosed within FIG. 1, a second improved conventional PRIOR ART hand strapping tool was developed and implemented, and this improved conventional PRIOR ART hand strapping tool is partially schematically disclosed within FIG. 2 and is generally indicated by the reference character 110. It is to be noted that a detailed description of the hand strapping tool 110 and its operative interaction with the overlapped end portions of the strapping material will not be set forth herein in view of the fact that such would simply be redundant and unnecessary because the basic tensioning and sealing operations of the two hand strapping tools 10,110 with respect to the overlapped end portions of the strapping material are substantially the same, and accordingly, only a description of the structural differences between the two hand strapping tools 10,110 will be set forth. In addition, it is also noted that corresponding parts of the hand strapping tool and the overlapped end portions of the strapping material will be designated by corresponding reference characters except that the reference characters in connection with the second conventional PRIOR ART hand strapping tool 110 will be within the 100 series.
More particularly, then, in order to overcome the various operational disadvantages or drawbacks characteristic of the conventional PRIOR ART hand strapping tool 10 disclosed within FIG. 1, the second improved conventional PRIOR ART hand strapping tool 110 is seen to comprise a base member 122 wherein one side or end portion of the base member 122 comprises an integrally formed, upwardly projecting lip member 136 wherein the uppermost crest portion 138 of the lip member 136 is adapted to be disposed slightly above the upper crest portions or extent of the lower gripper member teeth 132. As a result of the provision of such structure upon the base member 122, that is, in particular, to reiterate, as a result of the uppermost crest portion 138 of the lip member 136 being disposed slightly above the upper crest portions or extent of the lower gripper member teeth 132, it can readily be appreciated that those regions of the overlapped end portions 116,118 of the strapping material 114 which are disposed immediately adjacent to the upwardly projecting lip member 136 and which are disposed above the lower gripper member 128 will in effect be slightly spaced above the lower gripper member 128.
Accordingly, when the upper tensioning wheel 130 is lowered or moved downwardly so as to engage the overlapped end portions 116,118 of the strapping material 114 and to cooperatively engage the lower gripper member 128, those regions of the overlapped end portions 116,118 of the strapping material 114 which are disposed immediately adjacent to the upwardly projecting lip member 136 and which are disposed above the lower gripper member 128 will in effect be deflected slightly downwardly by means of the downwardly moving upper tensioning wheel 130 until those regions of the overlapped end portions 116,118 of the strapping material 114 engage the lower gripper member 128. Upon completion of the tensioning operation performed upon the overlapped end portions 116,118 of the strapping material 114, the upper tensioning wheel 130 is of course retracted or moved upwardly so as to return to its non-engagement position with respect to the overlapped end portions 116,118 of the strapping material 114 and the lower gripper member 128, and accordingly, again, due to the relative elevated disposition of the uppermost crest portion 138 of the lip member 136 with respect to the upper crest portions or extent of the lower gripper member teeth 132, those portions of the overlapped end portions 116,118 which are disposed adjacent to the lip member 136 and which were engaged between the upper tensioning wheel 130 and the lower gripper member 128 will likewise deflect slightly upwardly and thereby return to their original positions which were slightly spaced above the upper crest portions of the lower gripper member teeth 132.
Therefore, when the hand strapping tool 110 is to be removed from its operative position with respect to the package or article 112 and the overlapped end portions 116, 118 of the strapping material 114, the slight space defined between the undersurface of the lower one of the overlapped end portions 116,118 of the strapping material 114 and the upper surface or crest portions of the lower gripper member 128 will permit the hand strapping tool 110 to be more easily or readily removed from its engagement with the package or article 112 and the overlapped end portions 116,118 of the strapping material 114. However, even though the aforenoted structure facilitates the easier withdrawal of the hand strapping tool 110 from its engaged position with the package or article 112, it has been further discovered or experienced that due to the relatively high tightened or tensioned state of the strapping material 114 encircled around the package or article 112, and in particular, due to such relatively high tightened or tensioned state of the strapping material 114 engaged around the uppermost crest portion 138 of the lip member 136, the uppermost crest portion 138 of the lip member 136 will experience wear or erosion over time due to the relative repetitive sliding of the uppermost crest portion 138 with respect to the lower one of the overlapped end portions 116,118 of the strapping material 114 attendant multiple strapping operations performed by the hand strapping tool 110. Accordingly, over time, the elevational level of the uppermost crest portion 138 of the lip member 136 with respect to the elevational level of the upper crest portions of the teeth 132 of the lower gripper member 128 will in effect be lowered or reduced whereby a space will no longer be effectively defined between the undersurface portion of the lower one of the overlapped end portions 116,118 of the strapping material 114 and the lower gripper member teeth 132. Accordingly, the objective of having provided the upwardly projecting lip member 136 will in effect have been defeated. Under these circumstances, the upwardly projecting lip member 136 will have to be replaced, however, in view of the fact that the upwardly projecting lip member 136 is integral with the base member 122 of the hand strapping tool 110, the entire base member 122 must be replaced. This, however, entails a time-consuming and costly procedure.
A need therefore exists in the art for a new and improved hand strapping tool wherein the hand strapping tool can be in effect easily and readily removed from its engaged position with respect to the article or package being strapped as well as with respect to the tensioned overlapped end portions of the strapping material, while in effect also reducing or minimizing maintenance or replacement costs of the hand strapping tool components due to erosion or wear over time attendant the repetitive tensioning and sealing operations performed in connection with the tensioning and sealing of overlapped end portions of the strapping material.
Accordingly, it is an object of the present invention to provide a new and improved hand strapping tool.
Another object of the present invention is to provide a new and improved hand strapping tool wherein the hand strapping tool can be easily and readily removed from its engagement with respect to the article or package being strapped as well as with respect to the overlapped end portions of the tensioned strapping disposed about the article or package.
An additional object of the present invention is to provide a new and improved hand strapping tool wherein the hand strapping tool can be easily and readily removed from its engagement with respect to the article or package being strapped as well as with respect to the overlapped end portions of the tensioned strapping disposed about the article or package as a result of the provision of an upstanding lip member which creates or defines a space between the overlapped end portions of the tensioned strapping and the lower gripper member.
A further object of the present invention is to provide a new and improved hand strapping tool wherein the hand strapping tool can be easily and readily removed from its engagement with respect to the article or package being strapped as well as with respect to the overlapped end portions of the tensioned strapping disposed about the article or package as a result of the provision of an upstanding lip member which is integrally formed or provided upon the lower gripper member so as to create or define a space between the overlapped end portions of the tensioned strapping and the lower gripper member and which therefore also minimizes or reduces maintenance or replacement costs in view of the fact that if the upstanding lip member requirements replacement due to erosion attendant repetitive tensioning operations, only the lower gripper member needs to be replaced.
The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved hand strapping tool which comprises the incorporation therein of a lower gripper member wherein the lower gripper member is provided with an integral upwardly projecting lip portion. The upper surface of the upwardly projecting lip portion is disposed at an elevational level which is slightly above the elevational level of the upper crest portions of the teeth of the lower gripper member such that when the tensioning wheel is retracted upwardly back to its original inoperative position with respect to the lower gripper member, the upper surface of the upwardly projecting lip portion of the lower gripper member causes the overlapped end portions of the strapping material to be disposed slightly above the upper crest portions of the lower gripper member teeth. In this manner, the hand strapping tool can be readily removed relatively easily with respect to the package or article, and with respect to the tensioned overlapped end portions of the strapping material. In addition, should the upwardly projecting lip portion become worn due to erosion attendant repetitive tensioning operations and the relative sliding movement between the hand strapping tool and the tensioned overlapped end portions of the strapping material upon the conclusion of each strap tensioning operation, only the lower gripper member, and not the entire base member, needs to be replaced.